I wonder if Arborwear will ever make "tighty whities" for tree climbing?
This is fast becoming the thread on how to avoid the crunch.
Whaddya think Icabod?

I played around with your mods to the Tengu today. I really like the way these rubber bands worked out vs the tape.

Drainhook that is superb! I've got some old Big Shot tubing laying around, might be able to cut my rubber bands out of that.

It looks like you can move the rubber bands back to make it easier to take the pear off the harness. My pear never comes off but it would be nice to have the option.
-moss

I am glad you like this improvement moss. I found that by simply raising the band opposite the screw I was able rotate the pear enough to unscrew and install a grigri for use with the yoyo system.

Being able to completely remove the pear sure helps with donning the saddle while wearing bulky overalls.


I used the blue band-its that sherrill sells. I didn't get the tool, large snap-ring pliers work just fine.
http://www.sherrilltree.com/Professiona ... Bands-1150

Drainhook, that's an interesting improvement. I was thinking zip-ties might be an alternative to the tape, but they'd be too narrow. The bands you use spread out the force nicely. Are they easy to move? Do they stay put when the legstrap D's get shoved against them? By the way, I can unscrew the pear link enough to fit a GriGri on, with tape, so it might be a matter of placing the bands or tape right.

How do you like the orientation of the GriGri when attached directly to the pear link? To me, it's oriented a bit oddly, but it might work, going to try it out. You couldn't unclip from the rope, which is both good and bad. Good because, well, you can't accidentally fall, and bad because you can't switch ropes or rope ends easily. I guess you'd have to use a lanyard at the top of your pitch and keep advancing the TIP, climbing SRT yo-yo the whole time.

I attach the Grigri to the swivel on my pear with a carabiner. The swivel allows the Grigri to have a good orientation to the rope and the harness.
-moss

The bands on the legstraps are not easily moved, however the one band on the pear can be wiggled around easily enough. I have only tried the Tengu/yoyo combo with the grigri on the pear, and on the leg-strap D (like moss' friction hitch attachment point).
I must say that I like the way it climbs on the pear more than on the leg-strap D. I think it is because of the sit/stand motion. With the grigri attached lower, (leg strap) my body wants to tilt back when I am in the sit position.

I want to get a swivel, so I can attach the grigri to a biner, till then, what are the options with then tengu?
2 carabiners from the pear?
Leg strap D?
directly to the pear...

You definitely don't want to attach a Grigri to the legstrap D, that would pitch you back way too far.

A single biner from the Grigri to the pear works. The swivel is an enhancement, makes the Grigri play more friendly.

I made a cheapo swivel alternative by making a very short sling from tech cord, girthed a rated aluminum ring to one end and girthed the other end on to my pear. Then I'd attach a carabiner from the Grigri to the ring. It worked, allowed the Grigri to pivot but the Grigri ended up too high for my liking. Another problem was the sling would ungirth itself from the pear when it wasn't being used.

In general you wouldn't want to be opening the pear in the tree to take devices off or put them on, Once you're on rope pear stays closed.
-moss

No doubt, about not wanting to attach it to the legstrap D. The single biner with the grigri/tengu was pretty whacky feeling for me as well. Having the "twisting" of the biner/grigri connection is what I was looking to avoid. I guess that is why I have been yo-yoing in my rock harness more than my tengu

Gotta try to find a swivel on the cheap.

BTW moss, do you use your swivel for any other attachment than the grigri?

Just to be clear, when I'm climbing DRT I attach a biner holding one leg of the rope to my pear, the other leg of the rope is attached with the friction hitch anchored on a carabiner on my leg strap D, I never ever hang off just the leg strap D.
-moss

Yes, when I'm climbing both ends of the rope on a DRT traverse I may use it one of two ways:

1. Tied in traditional Blake's on both TIPs, put both biners on the swivel. This allows me to pivot under my ropes. For instance I might start the traverse facing one direction but may want to change position to make an easier landing at the other end of the traverse, or I might want to look at the view behind me as I cross, just pivot under the swivel to face the opposite direction

2. Using an e2e split tail on each TIP for a traverse, for my second TIP I clip the biner holding the hitch and the biner holding the standing leg of the rope into the swivel, helps separate the systems and makes it all play friendly going across.
-moss

I ran across something in the technical directions for the Microcender. After mentioning it won't hold in a fall (of course), it says to not use a lanyard between the harness and the Microcender. I think they put that in the instructions because a lanyard can go slack easily and that opens the potential for a fall, which can overload the cam. As we know, the device is only rated for 4KN on bigger rope. I don't think this is a potential problem with our climbing styles, but I was wondering what other people thought; also wondering if I interpreted the notice right. I figured you knowledgeable types would be able to inform me. Of course, the ultimate authority is Petzl (and gravity) and I'm not trying to suggest otherwise

http://www.petzl.com/files/all/technica ... 040598.pdf

Thanks for pointing that out John. I've looked around and can't find any mention anywhere as to why using a lanyard connection to the harness is a problem for the Microcender. I'm guessing your theory is correct, that a lanyard increases the risk of shock loading the ascender. So I guess we're back to the same question for all ascenders for SRT tree climbing use, none of them is good in a shock loading scenario but that's not what we do when we climb SRT.

Storrick describes the Microcender as indestructible. It will not break at 4kn, it will slip on the rope which is considered a virtue as opposed to cutting the rope. I back the Microcender with a hitch.
-moss

Great testing data here: Industrial rope access test document

Microcender slipped approx. 1 meter at 3kn dynamic load with nominal rope damage, the device was tested repeatedly and suffered no damage. The 1 meter slip represents shock absorption which is a good thing just as long as you don't hit a branch during the slip phase. After several 12kn load tests it appeared the cam was showing some wear. Petzl recommends retiring the device after one shock load (cover their butt), obviously the Microcender is very robust.

A lanyard from the Microcender to the harness is going magnify dynamic loading if the lanyard is slack when the shock occurs. However that means that the if that load is 3kn or greater that the ascender will slip and then grab when the force above 3kn is dissipated.

All kinds of interesting data in this document which some of you have probably already read...

In a dynamic loading scenario an Ushba cut the rope at 4kn and the device was too distorted to be used again.

Some great knot strength data (Double Overhand Loop or Barrel Knot did very well), was praised for its shock absorbing capability.

Good data on loading during ascent using two ascenders SRT. Peak loads were a little over 1kn during ascent load/unload cycles.
-moss

Wow, that is incredibly robust. I've got more respect for that little hunk of metal now! The cam design not cutting the rope seems like a really nice feature. I guess it lowers the hold strength of the ascender by about 2 kN, which is why most of Petzl's ascenders use teeth. I also am glad to hear the microcender outperforms the Ushba in that scenario. Nice to hear expensive titanium doesn't always win the day

I like the dynamic slip feature of the microcender, but I think it's of limited usefulness in a large fall. Of course, we shouldn't undergo them. I'll read through that PDF tonight, sounds good. I want to learn a bit more about the knots absorbing energy, too.